Coil



April 17, 1928.

H. D. CURRIER A COlL 272/527 727' ffz'fE/ZZZYIUFNEP Patented Apr, 17, 1928. M..

UNITED STATES 1,666,126 PATENT OFFICE.

HIRAM D. CURBIEB, OF CHICAGO, ILLINOIS, ASSIGNOR T0 KELLOGG SWITCHBOARD AND SUPPLY COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

COIL.

Application med october 1s, 1924. serial No. 744,465.

My invention relates to coils or transformers, and has to do more particularly with transformers of the air core type, which in the art of wireless or radio art, are known as radio frequency transformers and are used in circuits of radio receiving sets.

In transformers of the above type, the primary and secondary windings comprise a plurality of convolutions or turns of wire wound upon tubes of insulation material, or

a plurality of turns of wire are wound upon moulded members of insulating material. It has been found that large losses occur, due to leakage drainage of the coils and material capacity, owing to the fact that the convolutions of Wire are in contact with their supporting tubes or form and with each othenand an object of my invention is -to construct a coil which will obviate a largeV percentage of the loss found in coils of the prior art.

A feature of my invention is the provision of an improved coil of the above type, in which each individual convolution of the coils is equally spaced from its adjacent convolution, and in which each layer of convolutions is 'spaced from the adjacent layers of convolutions.

Another feature of my invention is the rovision of an improved coil construction, in which tiers of insulation strips are built up to form arms which are equally spaced apart, and at right angles to each other, and which strips are rovided with means for spacing the convo utions of a layer equally and in which the strips also equally space the layers of convolutions.

Another feature of my invention is the construction or building up of these arms to form a spider upon which the convolutions arc supported, so as to present a small contacting surface for each convolution of wire of the windings, so that only a small percent of the winding actually contacts with the supporting member or spider.

A further feature of my invention is thc means the convolutions 0f the windings play in securing the individual strips in relation to each other, and the way it secures the arms which forms the spider in position against movement to form a substantial winding.

A still further feature of my invention is the production of a coil in which the turns of wire are spaced from each other and the layers of wire are spaced from eachother to form a unitary self supporting structure without the use of any substance such as shellac or the like for holding the turns of wire in osition.

The eatures just mentioned, as well as others, relating to the details of construction and combination of parts will be hereinafter more particularly pointed out in the ensuing specification and appended claims.

For a better understanding of my invention reference may be had to the accompanying drawing in which like reference charactors in thc several views denote like parts, and in which:

Fig. l is a plan View of the transformer of my invention;

Fig. 2 is a right side vicw of Fig. 1;

Fig. 3 is a left side view of Fig. 1;

Fig. 4 is a sectional view along the line 4 4 of Fig. l;

Fig. 5 is a sectional vi 5-5 of Fig. 1;

Fig. 6 is a perspective view of the block or core about which the coil or transformer is wound, and

Fig 7 is a perspective view of one of the combined separator and spacer members.

Referring now more in detail to my invention as illustratedy in the accompanying drawings the transformcr of kmy invention comew along the line prises a primary winding P anda secondary winding S, and as the two windings P and S are similar in construction, a detailed description of the primary winding will suffice. The primary winding P of the transformer of my invention which is typical of both windings, comprises a plurality of convolutions T of wire in layers L, in which each adjacent turn T of a layer L is equally spaced apart and each layer L of convolutions of the winding is also separated an equal distance. To accomplish this, I have devised a novel method of construction in which the primary winding P of the transformer cornprises a core 2 of suitable insulation material, such as hard rubber. The core 2 is square in shape with its corners chamfered to present angular faces 3, 4., 5 and 6, for purposes as will presently be described.

The winding ,is built up of a plurality of layers L of convolutions T and to equally space adj acent'turns in a layer L and space the successive layers L, I provide separate strips 7, and to construct a transformer rof s neoaieo this type, a suitable fixture is provided. The iiXture is of suitable construction comprising tWo sections, each ot Which is provided with a body portion and tour integrally formed extending` arms at right angles to each other. The sections when placed together in matched relation to clamp the core 2 between the body portions ot the fixture sections also places the extending arms in matched relation: to torm channels of a sise to permit the insertion et the rectangular separator strips 7 rlhe seoarator strips 7, one olf which is illustrated in perspective iu Fig'. 7, is made of a rectangular strip oit insulation material, such as hard rubber, the face 8 ot which is provided withA parallel slots 9, l0 and 11. The assembly xture, as before described, clamps the core 2 in position, and with the core 2 thus clfamiiied a sep arator strip 7, as illustrated, is positioned in the channel ot' an arm et the fixture with its bottom face 12 resting,` against the angular 'face 3l oft the core 2. 'lhe inside terminal ot the Winding lll is secured to the strip 7 by threading the end through an oriiice 30' in the strip 7 to secure the same in position. The Wire 13 is now laid in the slot 9 oi the strip 7, and with lthis strip 7 in position with the Wire 13 in the slot 9, the fixture is turned to present the other three arms oi the fixture in succession` to permit separator strips 7 to be positioned in the channels otthe arms Wit-.h their bottom ifaces l2 resting against the angular tacos 4l, 5 and 6 of the core Q.

r The Wire 13 is laid in the slots 9 ot these three strips 7 that are placed in succession in the remaining three arms of the tiz'rture, and the continued turning of the fixture will permit the wire 13 to be laid in the slots 10 and ll of the four strips 7, Which rest against the respective angular iaces 3, Il, 5 and 6 ot the core 2. n

Thus far described, the irst layer L has been placed on the core 2 which consists of three turns or convolutions T. To place the next layer L of convolutions T on the core 2, a strip 7 is positioned in the channel` et the arm oi the Alirture that received the strip 7,1to which the inner terminalA ot the Wind ing `W is secured, the second strip 7 resting in position With its bottom'tace 12 resting` against the tace 8 et the first strip 7. rllhe Wire 13 is new laid in the slot 1l of the second strip 7, and the lirzture is then turned to present the other three arms of the xture in succession to permit the other three strips 7 to be positioned in the channels with their bottom faces 12 resting against the faces 8 of the strips 7 already in position which support the first layer ll of convoiutions T. The Wire 13 is now laid in the slots 11, 10 and 9 of this second tier et strips 7, to complete the second layer L ot the convolutions T. c

From the above description, it is readily apparent the successive tiers of strips 7 are positioned in the channels of thearms ot the fixture and the Wire 13 laid in the slots 9, l() and 11, from lett to right, and vice versa, for the required number are to be placed upon the supporting,- core 2. lilfhen the required number of turns has been completed, ythe outside end of the Winding` is threaded through an oriiice 30 in the strip 7 et the last tier, thus securing,` it against movement.,

rlhe above method of constructioi'i in which four arms, a, '6, c and Z are built up oit superimposed strips 7, will torni a spider in which the arms a, and extend outward from the supporting core 2, at right angles to the outwardly extending` arms 0 and 1. The Wire i3 as it is placed in the slots'oi the strips 7 in layers l; is held. taut by suitable means during the Winding operation ot' the coil, thus producing` a clamping eiiect upon each strip7, as it is superimposed on a strip already in position, thus each arm is seltsupporting, each being built up oiI tiers ol strips 7, and the lateral movement oft' the strips 7 in relation to each other is prevented by means of the pressure exerted by the convolutions ll oi a. layer L upon its supporting' strips 7. volfutions T ot the layers L also prevents tilting or movement of thearm-s a, Z), c and el, as a whole, on the cores. With the vconvolutions of the Winding oi:n each layer L resting,` in the slots 9, 10 andv 1l. oi? the strips 7, it is impossible to displace the convolutions from their lined spaced relation With each other, as each succeeding` strip 7 as it is'placed above the other prevei'its any movement of the lindividual convolution, .From the toregoing it Will be noted that the primary Winding l? square in form and they convolutions T only engage the supporting,l arms a, h, c and (Z, Which are built up of tiers oi",l strips 7 at these tour points et contact which points ot Contact are the slots 9, 10 and 11 in the strip 7. l have also produced a coilV inV which each convolutionv T is equally spaced from its adjacent convolution T by means ot the separation between the slots t), 1() and l1 oi the strips 7 and in which the successive laf/*ers L are also equally spacedk apart by means of the separator strips 7.

While l have illustrated the strips 7 with the slots to permit each layer olE convolu tions r.l tohave three turns l do not ,Wish to be limited to the exact number as a larger strip 7 mayl be employed with a greater number of slots to accommodate a greater number oit convolutions per layer to increase the number of turns Without departing from the spirit of the invention. It may also be seen that I have constructed a. coil Which is substantially built and which may be handled Without disarranging the Winding or shitting oi the arms or spider as a Whole ot turns T Which This pressure exerted by the con-v Fit) lllfi lltl due to the binding effect of the convolutions on the individual strips 7 and the arms a, I), c and d which are built up of a plurality of strips 7.

As I have described in detail the construction of the primary Winding P a detailed description ofthe secondary winding S is not necessary only in so far as to say that the secondary winding S is also supported on a core 2 and wound in a similar manner to produce a square coil Winding S. To associate the primary Winding P and the secondary winding S with each other, a suitable spacer member 2l is placed between the cores 2 and 2 of the prilnary and secondary windings P and S, and a stud 22 passing through orifices 23, 24 and 25 in the core 2; spacer member 2l and core 2 clamp the two coils P and S together by means oi a screw 26 which has screw-threaded engagement with a tapped orifice 27. in the end ot the stud 22, a suitable washer 2S being placed between the head of the screw 26 and the face of' the core 2. The other endI of the stud 22 is provided with a tapped orifice and may be secured to the supporting panel by a suitable screw, which has screw-threaded engagement with the tapped orifice in that end of the stud.

By this method of construction I eliminate the large leakage or drainage of the prior coils in which the turns ot wire were in direct contact with the supporting tube or member with each other throughout the entire length thereof, and I also reduce the mutual capacity et'. the coil.

It is readily apparent that I may regulate the coupling of the coils by separating them any desired amount, and the means to accomplish this end may be made adjustable it' desired. Further it is obvious that I may use just one coil for an inductance instead ot using two coils for a transformer.

lVhile I have described a particular form of coil it is to be understood that changes and modifications will readily suggest themselves to those skilled in the art and I therethe spirit and scope of the appended claims.

Having described my invention what I claim as new and desire to secure by United States Letters Patent is: y

l. In a device of the character described including a rectangular shaped core provided with chamfered edges to form angular faces diametrically opposite, strips sustrips in position to `form a self-supporting.

structure whereby said Winding maintains said strips and said strips support said winding to form a coil.

2. In a device of the character described .including a rectangular core provided with vchamfered edges to form angular faces diametrically opposite, strips superimposed upon said diametrically opposite angular faces of said rectangular core to form arms at right angles to adjacent arms and parallel to thel opposite arm, slots in each of the superimposed strips in which is wound a plurality of turns of wire to form a rectangular shaped winding, said slots maintaining said turns in spaced relation and said strips maintaining the layers in spaced relation to each other and said winding being adapted to bind said strips to form a self-supporting structure.

3. In a device ot the character described including a pair of rectangular shaped cores having orifices and each provided with chamiered edges to form angular faces, strips superimposed upon said angular faces oli each rectangular core to form arms at right angles to adjacent arms and parallel to the opposite arm, slots in said strips, a winding angular' in form supported in said slots in spaced relation, said winding having a binding effect for maintaining said strips in fixed relation to each other against movement and for maintaining said Varm at right angles to each other, a spacing member having a central orifice, adapted to be secured between said rectangular cores, a stud adapted to enter said orifices and a screw member having screw threaded engagement with an orifice in said stud for securing said cores and their supported windings in position whereby the windings supported on one of said cores are parallel to the windings supported on the other of said cores.

- Signed by me at Chicago, county of Cook and State of Illinois, this 16th day of October, 1924.

HIRAM D. CURRIER. 

